I had asked a question recently about have ALC problems with digital modes and did receive some suggestions privately. I had a slow "oscillation" of the ALC over several seconds per oscillation with the ALC peaking and then dropping back to zero and then going up to maximum again.
Initially I had thought this was only on 80 meters, but as it turned out, I was also present whenever I was using my multiband dipole which is directly overhead. My ground mounted vertical, which is 150 feet out from the shack, caused no noticeable problem. As I had a fairly long shielded cable (6 feet) running from the sound card to the ACC1 socket on the ICOM 756 Pro II, I decided to try some toroid cores. No noticeable change. I did notice that I could reduce the noise if the cables just happened to go over the top of the rig's cabinet. Probably a capacitance to ground effect? I then took an Amidon rod and wrapped a few turns around it and did notice a reduction in the problem. So I wrapped about 20 turns on the core and the RFI appears to be completely gone. 73, Rick, KV9U Andrew O'Brien wrote: > Interesting. Anyone care to explain why RF would cause this ALC issue? > > On 2/13/06, *Mel* <[EMAIL PROTECTED] > <mailto:[EMAIL PROTECTED]>> wrote: > > Hello Tim, TG6124, > > I solved the problem and I think it may have been RF. The day before > the antenna had been playing up and I moved the coax cables and in > doing so placed the cables from the ACC1 to the ISO box in a place > where they seem to have caused this trouble. I separated them and the > problem seems to have gone away. > > Many thanks for your response, I was surprised to have one as most of > the correspondence seems to be involved with only one subject. > > Kind regards, Mel G0GQK > > > Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
